Cell and Molecular Biology Practice Exam Quiz
Which of the following is not a major component of the plasma membrane?
A) Phospholipids
B) Cholesterol
C) Nucleic acids
D) Proteins
What is the primary function of ribosomes in a eukaryotic cell?
A) DNA replication
B) Protein synthesis
C) Energy production
D) Lipid metabolism
What structure is responsible for packaging and modifying proteins in the cell?
A) Nucleus
B) Mitochondrion
C) Golgi apparatus
D) Endoplasmic reticulum
The process by which mRNA is synthesized from a DNA template is known as:
A) Translation
B) Replication
C) Transcription
D) Cloning
Which enzyme is responsible for unwinding the DNA during replication?
A) RNA polymerase
B) DNA polymerase
C) Helicase
D) Ligase
In which part of the cell does DNA replication occur?
A) Nucleus
B) Cytoplasm
C) Mitochondria
D) Ribosome
Which of the following molecules is used as the template for protein synthesis during translation?
A) mRNA
B) tRNA
C) DNA
D) rRNA
The sequence of three nucleotides in mRNA that codes for a specific amino acid is known as:
A) Codon
B) Anticodon
C) Exon
D) Intron
What is the main function of the endoplasmic reticulum (ER)?
A) Synthesis of proteins and lipids
B) Storage of genetic information
C) Production of energy
D) Detoxification
Which of the following best describes the function of mitochondria?
A) Storage of calcium ions
B) Production of ATP through cellular respiration
C) Protein synthesis
D) DNA replication
The molecular tool that allows for the copying of a specific gene segment in the laboratory is:
A) Polymerase chain reaction (PCR)
B) Gel electrophoresis
C) DNA microarray
D) Restriction enzyme
Which organelle contains its own DNA and is involved in energy production?
A) Ribosome
B) Mitochondrion
C) Lysosome
D) Golgi apparatus
The genetic code is read in sets of how many nucleotides?
A) One
B) Two
C) Three
D) Four
What is the primary function of lysosomes in the cell?
A) Protein synthesis
B) Storage of genetic material
C) Digestion of macromolecules
D) ATP production
Which of the following is the correct order of the central dogma of molecular biology?
A) Transcription → Translation → Replication
B) Replication → Transcription → Translation
C) Translation → Replication → Transcription
D) Translation → Replication → Transcription
In which phase of the cell cycle does DNA replication occur?
A) G1 phase
B) S phase
C) G2 phase
D) M phase
Which of the following is responsible for attaching amino acids to their corresponding tRNA molecules?
A) DNA polymerase
B) Aminoacyl-tRNA synthetase
C) RNA polymerase
D) Ribosome
Which of the following sequences of nucleotides would be complementary to the DNA sequence 3′-ATCG-5′?
A) 3′-TAGC-5′
B) 5′-TAGC-3′
C) 3′-GCTA-5′
D) 5′-GCTA-3′
What process is responsible for generating genetic diversity during meiosis?
A) Mitosis
B) Independent assortment
C) DNA replication
D) Transcription
The structure that contains the genetic material in eukaryotic cells is the:
A) Nucleoid
B) Nucleus
C) Mitochondrion
D) Ribosome
Which of the following is a characteristic feature of eukaryotic cells, but not prokaryotic cells?
A) Cell membrane
B) Nucleus
C) Ribosomes
D) Cytoplasm
During which phase of the cell cycle does the cell prepare for mitosis?
A) G0 phase
B) G1 phase
C) G2 phase
D) S phase
Which of the following is not a function of the cytoskeleton?
A) Maintain cell shape
B) Facilitate cell movement
C) Protein synthesis
D) Organize intracellular components
Which type of RNA is responsible for transporting amino acids to the ribosome?
A) mRNA
B) tRNA
C) rRNA
D) siRNA
What is the role of enhancers in gene regulation?
A) They bind to promoter regions to increase gene expression
B) They degrade mRNA
C) They inhibit transcription
D) They assist in DNA replication
Which of the following techniques is used to separate proteins based on their size?
A) PCR
B) Western blotting
C) Gel electrophoresis
D) Northern blotting
What type of bond holds the two strands of DNA together?
A) Ionic bond
B) Hydrogen bond
C) Covalent bond
D) Disulfide bond
What is the function of restriction enzymes in molecular biology?
A) To replicate DNA
B) To cut DNA at specific sequences
C) To transcribe RNA
D) To synthesize proteins
What is the first step in the process of gene expression?
A) Translation
B) Replication
C) Transcription
D) Protein folding
Which of the following processes allows for the movement of large molecules like proteins across the plasma membrane?
A) Simple diffusion
B) Facilitated diffusion
C) Active transport
D) Endocytosis
What is the function of the nuclear pore complex?
A) DNA replication
B) RNA processing
C) Transport of molecules in and out of the nucleus
D) Protein folding
Which of the following is a characteristic of prokaryotic cells?
A) They have a nucleus
B) They contain membrane-bound organelles
C) They lack a defined nucleus
D) They are multicellular
Which molecule directly provides energy for most cellular processes?
A) DNA
B) ATP
C) mRNA
D) NADPH
The process of converting mRNA into a functional protein is known as:
A) Replication
B) Translation
C) Transcription
D) Gene editing
Which of the following types of RNA is a part of the ribosome?
A) mRNA
B) tRNA
C) rRNA
D) snRNA
In the context of gene expression, what is the role of silencers?
A) To enhance gene expression
B) To silence gene expression
C) To transcribe mRNA
D) To catalyze DNA replication
Which of the following is a part of the cell cycle in which the cell does not divide?
A) Prophase
B) Interphase
C) Telophase
D) Metaphase
What is the function of the protein p53 in a cell?
A) DNA replication
B) Regulation of the cell cycle and apoptosis
C) RNA processing
D) Protein translation
What structure is responsible for maintaining the shape and rigidity of plant cells?
A) Nucleus
B) Mitochondria
C) Chloroplast
D) Cell wall
What does the term “homologous recombination” refer to?
A) The process by which homologous chromosomes are separated during meiosis
B) The exchange of genetic material between similar chromosomes during meiosis
C) The process of DNA replication
D) The formation of proteins from RNA
Which organelle is involved in the detoxification of harmful substances in the cell?
A) Peroxisomes
B) Nucleus
C) Mitochondrion
D) Lysosome
Which of the following is a key characteristic of apoptosis?
A) Uncontrolled cell division
B) Cell shrinkage and DNA fragmentation
C) Increased protein synthesis
D) Unregulated protein degradation
What is the role of telomerase in cellular replication?
A) To extend the telomeres and prevent chromosome shortening
B) To replicate the entire genome
C) To synthesize mRNA
D) To degrade defective proteins
Which of the following is a key difference between meiosis and mitosis?
A) Mitosis results in two daughter cells, while meiosis results in four daughter cells
B) Meiosis involves the separation of sister chromatids, while mitosis does not
C) Meiosis occurs in somatic cells, while mitosis occurs in gametes
D) Mitosis results in haploid cells, while meiosis results in diploid cells
The term “exon” refers to:
A) A non-coding region of a gene
B) A coding region of a gene
C) A promoter region of a gene
D) A repressor site in DNA
Which of the following describes a point mutation?
A) A change in a single nucleotide in the DNA sequence
B) The deletion of a segment of a chromosome
C) The insertion of a large DNA fragment
D) The exchange of genetic material between non-homologous chromosomes
What is the purpose of the CRISPR-Cas9 system?
A) DNA sequencing
B) Gene editing
C) Protein synthesis
D) RNA interference
Which of the following is an example of a post-translational modification?
A) RNA splicing
B) mRNA capping
C) Phosphorylation of a protein
D) DNA replication
Which of the following organelles is involved in lipid synthesis?
A) Golgi apparatus
B) Smooth endoplasmic reticulum
C) Ribosome
D) Nucleus
What is the main function of the nucleolus within the nucleus?
A) Packaging and sorting proteins
B) Synthesis of ribosomal RNA (rRNA)
C) DNA replication
D) Energy production
What is the term used to describe a group of genes that are regulated together and often transcribed as a single unit?
A) Operon
B) Chromosome
C) Codon
D) Gene cluster
Which of the following is an example of a genetic disorder caused by a mutation in mitochondrial DNA?
A) Down syndrome
B) Huntington’s disease
C) Leber’s hereditary optic neuropathy
D) Cystic fibrosis
The process of RNA splicing involves the removal of which sequence?
A) Exons
B) Codons
C) Introns
D) Promoters
Which of the following is responsible for the folding and modification of proteins after translation?
A) Nucleus
B) Ribosome
C) Golgi apparatus
D) Endoplasmic reticulum
What is the role of microtubules in the cell?
A) DNA replication
B) Protein synthesis
C) Cell division and transport of organelles
D) mRNA synthesis
What is the significance of the 5′ cap on eukaryotic mRNA?
A) It helps in mRNA degradation
B) It assists in mRNA export from the nucleus
C) It prevents mRNA splicing
D) It promotes the binding of the ribosome for translation
Which of the following best describes the role of G-proteins in cellular signaling?
A) They bind to and stabilize mRNA
B) They activate or inhibit enzymes in response to external signals
C) They facilitate transcription in the nucleus
D) They degrade proteins in the cytoplasm
In which cellular process do sister chromatids separate and move toward opposite poles of the cell?
A) Telophase
B) Metaphase
C) Anaphase
D) Prophase
What is the function of the signal recognition particle (SRP) during protein synthesis?
A) To deliver amino acids to the ribosome
B) To bind to the mRNA and initiate translation
C) To target proteins to the endoplasmic reticulum
D) To assemble ribosomal subunits
Which of the following processes occurs in the cytoplasm?
A) DNA replication
B) mRNA transcription
C) Translation of proteins
D) rRNA synthesis
What type of bond connects the two strands of a DNA molecule?
A) Ionic bond
B) Covalent bond
C) Hydrogen bond
D) Peptide bond
What is the primary function of the rough endoplasmic reticulum (ER)?
A) Lipid synthesis
B) Protein synthesis and modification
C) Detoxification of drugs
D) Storage of calcium ions
What is the role of the ribosome in the cell?
A) Synthesize lipids
B) Synthesize proteins
C) Replicate DNA
D) Generate ATP
Which of the following is a characteristic of a lysosome?
A) It contains digestive enzymes that break down waste materials
B) It is involved in the synthesis of ribosomal RNA
C) It synthesizes lipids
D) It contains genetic material
Which of the following is true about glycolysis?
A) It occurs in the mitochondria
B) It requires oxygen
C) It breaks down glucose into pyruvate
D) It produces a large amount of ATP
What is the role of cyclins in the cell cycle?
A) They help in the repair of damaged DNA
B) They regulate the progression of the cell cycle
C) They synthesize mRNA
D) They promote apoptosis
What is the function of the Golgi apparatus?
A) Synthesis of proteins
B) Packaging and transport of proteins and lipids
C) Conversion of glucose to ATP
D) Regulation of gene expression
Which of the following is a function of microfilaments in the cytoskeleton?
A) Form the mitotic spindle
B) Maintain cell shape and facilitate cell movement
C) Provide structural support for the nucleus
D) Transport organelles
What is the first step in the process of translation?
A) Elongation of the polypeptide chain
B) Binding of mRNA to the ribosome
C) Folding of the protein
D) Binding of tRNA to the mRNA codon
Which of the following molecules is responsible for transferring amino acids to the ribosome during protein synthesis?
A) mRNA
B) tRNA
C) rRNA
D) DNA
What is the function of the telomere?
A) It prevents the loss of genetic information during DNA replication
B) It regulates gene expression
C) It aids in protein folding
D) It helps in the transcription of mRNA
Which of the following best describes the function of the spliceosome?
A) It adds a 5′ cap to mRNA
B) It removes introns from pre-mRNA
C) It synthesizes ribosomal RNA
D) It binds mRNA to the ribosome
Which process involves the movement of molecules from a region of high concentration to a region of low concentration without the use of energy?
A) Active transport
B) Facilitated diffusion
C) Osmosis
D) Simple diffusion
Which organelle is responsible for the production of ATP?
A) Mitochondria
B) Nucleus
C) Endoplasmic reticulum
D) Golgi apparatus
In which phase of the cell cycle does DNA replication occur?
A) G1 phase
B) S phase
C) G2 phase
D) M phase
What is the role of histones in the nucleus?
A) To form the mitotic spindle
B) To bind to DNA and help in the formation of chromatin
C) To synthesize mRNA
D) To aid in protein synthesis
Which of the following is a feature of eukaryotic cells but not prokaryotic cells?
A) Cytoplasm
B) Ribosomes
C) Membrane-bound organelles
D) Circular DNA
What is the purpose of PCR (Polymerase Chain Reaction)?
A) To amplify a specific DNA sequence
B) To synthesize proteins
C) To sequence RNA
D) To replicate the entire genome
Which of the following is an example of a point mutation?
A) Deletion of a nucleotide
B) Insertion of a nucleotide
C) A change in a single nucleotide pair
D) Translocation of a gene
What does the term “genetic recombination” refer to?
A) The replication of genetic material
B) The exchange of genetic material between chromosomes
C) The copying of mRNA to DNA
D) The mutation of a gene
What is the process of transcribing DNA into RNA called?
A) Replication
B) Translation
C) Transcription
D) Mutation
Which of the following is involved in the formation of the mitotic spindle?
A) Microtubules
B) Actin filaments
C) Intermediate filaments
D) Ribosomes
What is the function of the protein complex known as the proteasome?
A) To degrade unneeded or damaged proteins
B) To replicate DNA
C) To transport proteins to the Golgi apparatus
D) To synthesize mRNA
What structure helps cells move through their environment?
A) Nucleus
B) Cilia and flagella
C) Lysosomes
D) Mitochondria
Which of the following is true regarding a codon?
A) It is a three-nucleotide sequence that codes for an amino acid
B) It is a type of RNA molecule
C) It is a mutation in the gene sequence
D) It is the site where transcription occurs
In which of the following stages of mitosis do the chromosomes line up in the center of the cell?
A) Anaphase
B) Telophase
C) Metaphase
D) Prophase
Which of the following enzymes is responsible for unwinding DNA during replication?
A) DNA polymerase
B) Helicase
C) Ligase
D) RNA polymerase
What is the role of the transcription factor in gene expression?
A) To transport RNA to the cytoplasm
B) To bind to DNA and regulate transcription
C) To degrade defective proteins
D) To catalyze protein folding
What is the function of tRNA during translation?
A) It carries the genetic code from DNA to RNA
B) It catalyzes the formation of peptide bonds
C) It carries amino acids to the ribosome
D) It unwinds the DNA helix
What is the primary function of the smooth endoplasmic reticulum (ER)?
A) Protein synthesis
B) Lipid synthesis and detoxification
C) RNA processing
D) Protein folding
Which of the following is true about a plasmid?
A) It is a structure found in the nucleus of eukaryotic cells.
B) It is a small, circular DNA molecule found in bacteria.
C) It is a protein that aids in DNA replication.
D) It is a type of RNA involved in protein synthesis.
Which type of RNA carries the genetic information from the DNA to the ribosome?
A) tRNA
B) rRNA
C) mRNA
D) siRNA
What is the main function of the centrosome in eukaryotic cells?
A) Protein synthesis
B) Organization of microtubules during cell division
C) Synthesis of lipids
D) Regulation of gene expression
In which of the following processes is ATP not directly involved?
A) Active transport
B) Protein synthesis
C) DNA replication
D) Simple diffusion
What is the function of DNA polymerase during DNA replication?
A) To unwind the DNA strands
B) To synthesize the new DNA strand by adding nucleotides
C) To remove primers from the DNA strand
D) To join Okazaki fragments
Which of the following statements about mitochondria is true?
A) Mitochondria are the site of protein synthesis in the cell.
B) Mitochondria contain their own DNA and can replicate independently.
C) Mitochondria are involved in lipid synthesis.
D) Mitochondria store genetic information in the form of RNA.
Which of the following is a feature of an enzyme-catalyzed reaction?
A) Enzymes are consumed in the reaction.
B) Enzymes increase the activation energy of the reaction.
C) Enzymes are specific to their substrates.
D) Enzymes are a form of RNA.
Which type of cell signaling involves a signal molecule binding to a receptor on the surface of the cell?
A) Autocrine signaling
B) Paracrine signaling
C) Juxtacrine signaling
D) Endocrine signaling
Which structure is responsible for maintaining the shape and mechanical strength of the cell?
A) Ribosome
B) Cytoskeleton
C) Nucleolus
D) Smooth ER
Which of the following best describes the process of apoptosis?
A) Controlled cell death
B) Cell division
C) DNA replication
D) Activation of cell signaling pathways
What is the role of the chaperone protein in the cell?
A) To facilitate protein folding
B) To replicate DNA
C) To transport proteins across the cell membrane
D) To break down damaged proteins
Which of the following processes involves the transfer of electrons in cellular respiration?
A) Glycolysis
B) Krebs cycle
C) Electron transport chain
D) All of the above
What is the primary function of the nuclear envelope?
A) To synthesize ribosomal RNA
B) To separate the nucleoplasm from the cytoplasm
C) To store genetic information
D) To replicate DNA
Which of the following is the correct sequence for the flow of genetic information?
A) RNA → DNA → Protein
B) DNA → RNA → Protein
C) Protein → RNA → DNA
D) DNA → Protein → RNA
What is the function of a promoter region in a gene?
A) It initiates transcription of the gene.
B) It serves as a binding site for ribosomes.
C) It ensures proper protein folding.
D) It regulates the rate of protein synthesis.
What type of bond forms between amino acids during protein synthesis?
A) Hydrogen bond
B) Ionic bond
C) Peptide bond
D) Disulfide bond
Which of the following is involved in regulating gene expression at the level of transcription?
A) Ribosome
B) RNA polymerase
C) DNA ligase
D) tRNA
Which of the following correctly describes the function of an enhancer in gene regulation?
A) It suppresses transcription of the gene.
B) It helps to stabilize the DNA double helix.
C) It binds to transcription factors to increase gene expression.
D) It is a sequence where RNA polymerase binds to begin transcription.
In a prokaryotic cell, where does transcription occur?
A) Mitochondrion
B) Cytoplasm
C) Nucleus
D) Nucleoid
Which of the following is a mechanism by which cells communicate with each other?
A) DNA replication
B) Protein synthesis
C) Cell signaling
D) Cellular respiration
What is the primary role of the smooth endoplasmic reticulum in cells?
A) Protein synthesis
B) Lipid synthesis and detoxification
C) Sorting and packaging proteins
D) Cellular respiration
Which of the following is a feature of the quaternary structure of a protein?
A) It involves the sequence of amino acids.
B) It is the three-dimensional shape formed by a single polypeptide chain.
C) It involves multiple polypeptide chains interacting.
D) It is the folding of a polypeptide into a helix or sheet.
What is the main function of the ribosome in the cell?
A) To store genetic information
B) To synthesize proteins
C) To maintain cell shape
D) To regulate gene expression
During which stage of the cell cycle does the cell grow and prepare for DNA replication?
A) G0 phase
B) G1 phase
C) S phase
D) G2 phase
What is the primary purpose of the mitochondria in eukaryotic cells?
A) To store genetic information
B) To synthesize proteins
C) To generate ATP through cellular respiration
D) To synthesize RNA
Which of the following proteins is involved in DNA replication by synthesizing new DNA strands?
A) Helicase
B) DNA polymerase
C) Ligase
D) Topoisomerase
Which of the following is true about the process of translation?
A) It occurs in the nucleus.
B) It involves the synthesis of RNA from a DNA template.
C) It involves the synthesis of a protein from an mRNA template.
D) It is part of the cell cycle.
In which of the following does the cell spend most of its life cycle?
A) Prophase
B) Interphase
C) Metaphase
D) Anaphase
What is the function of the 5′ cap in mRNA processing?
A) To protect mRNA from degradation
B) To facilitate the attachment of ribosomes during translation
C) To remove introns from the mRNA
D) To guide the mRNA to the Golgi apparatus
Which type of genetic mutation results in the insertion of an extra nucleotide into the DNA sequence?
A) Substitution
B) Deletion
C) Insertion
D) Translocation
Which of the following is NOT a function of the Golgi apparatus?
A) Protein modification
B) Protein packaging
C) Protein synthesis
D) Lipid synthesis
Which of the following structures is responsible for protein sorting and packaging?
A) Golgi apparatus
B) Lysosomes
C) Mitochondria
D) Ribosomes
The process by which RNA is synthesized from a DNA template is called:
A) Replication
B) Transcription
C) Translation
D) Replication and Transcription
Which of the following statements about the plasma membrane is true?
A) It is composed primarily of proteins and carbohydrates.
B) It is composed primarily of a phospholipid bilayer.
C) It is a rigid structure that prevents any movement.
D) It allows only ions to pass through it.
What is the main function of tRNA in protein synthesis?
A) To catalyze the formation of peptide bonds
B) To carry amino acids to the ribosome
C) To provide the instructions for protein synthesis
D) To bind to the mRNA sequence and prevent translation
Which of the following is the correct order of events in the cell cycle?
A) G1 → S → G2 → M → G0
B) S → G2 → G1 → M
C) M → G1 → S → G2
D) G1 → S → G2 → M
What is the function of a ribosome in the cell?
A) To package proteins for export
B) To store genetic material
C) To synthesize proteins
D) To provide energy for cellular processes
Which enzyme is responsible for unwinding the DNA double helix during DNA replication?
A) DNA polymerase
B) Helicase
C) Ligase
D) Topoisomerase
In the process of glycolysis, one molecule of glucose is converted into:
A) Two molecules of pyruvate
B) Two molecules of acetyl-CoA
C) Two molecules of ATP
D) One molecule of citric acid
What role does the smooth endoplasmic reticulum (SER) play in the cell?
A) Protein synthesis
B) Lipid and steroid hormone synthesis
C) Storage of genetic information
D) Packaging of proteins for secretion
The energy currency of the cell is:
A) Glucose
B) ATP
C) NADPH
D) GTP
Which of the following is the main function of the lysosome?
A) Protein synthesis
B) Storage of genetic material
C) Breakdown of cellular waste and foreign material
D) Transport of proteins
What is the primary function of the mitochondria in eukaryotic cells?
A) Synthesis of ribosomal RNA
B) Protein degradation
C) Production of ATP through cellular respiration
D) Detoxification of harmful substances
Which type of RNA is involved in bringing amino acids to the ribosome during translation?
A) mRNA
B) tRNA
C) rRNA
D) siRNA
Which of the following is a feature of prokaryotic cells?
A) A nucleus
B) Mitochondria
C) A plasma membrane
D) A large central vacuole
What is the function of the nuclear pores in eukaryotic cells?
A) To store genetic material
B) To regulate the movement of molecules in and out of the nucleus
C) To synthesize RNA
D) To break down cellular waste
The primary structure of a protein refers to:
A) The three-dimensional shape of the protein
B) The sequence of amino acids in the protein
C) The interactions between different protein subunits
D) The folding of the protein into a functional shape
In which of the following processes is oxygen used to produce ATP?
A) Glycolysis
B) Fermentation
C) Citric acid cycle and oxidative phosphorylation
D) Transcription
Which of the following is true about the process of translation?
A) It occurs in the nucleus of the cell.
B) It involves the synthesis of an RNA molecule.
C) It occurs in the cytoplasm at the ribosomes.
D) It produces tRNA from an mRNA template.
What is the function of a promoter sequence in DNA transcription?
A) It increases the rate of translation.
B) It serves as a binding site for RNA polymerase.
C) It terminates the transcription process.
D) It removes introns from the RNA.
Which of the following is true about the genetic code?
A) It is universal across all organisms.
B) It is used only in prokaryotic cells.
C) It is the same for RNA and DNA.
D) It includes stop codons that do not encode amino acids.
The enzyme that is responsible for adding nucleotides during DNA replication is:
A) DNA polymerase
B) RNA polymerase
C) Ligase
D) Helicase
Which of the following is the correct sequence of events in DNA replication?
A) Transcription → Translation → Replication
B) Replication → Transcription → Translation
C) Transcription → Replication → Translation
D) Translation → Replication → Transcription
What is the main purpose of the citric acid cycle in cellular respiration?
A) To generate ATP directly
B) To reduce NAD+ to NADH and FAD to FADH2
C) To produce glucose for energy
D) To regenerate oxygen for the electron transport chain
Which of the following is a mechanism of gene regulation in eukaryotes?
A) DNA replication
B) Transcriptional control
C) DNA repair
D) Translation of ribosomal RNA
What is the function of the 3′ poly-A tail in eukaryotic mRNA?
A) To stabilize the mRNA and aid in its export from the nucleus
B) To bind to ribosomes for translation
C) To remove introns from the mRNA
D) To provide a site for RNA polymerase binding
Which of the following describes the function of the nuclear envelope in eukaryotic cells?
A) It provides a barrier to protect the DNA from mutations.
B) It controls the entry and exit of molecules to and from the nucleus.
C) It synthesizes RNA molecules.
D) It helps in protein synthesis.
Which process occurs in the cytoplasm and produces ATP without the use of oxygen?
A) Glycolysis
B) Krebs cycle
C) Electron transport chain
D) Oxidative phosphorylation
The process of cell division in prokaryotes is called:
A) Mitosis
B) Meiosis
C) Binary fission
D) Cytokinesis
Which of the following organelles is involved in the synthesis of ribosomal RNA (rRNA)?
A) Mitochondria
B) Nucleolus
C) Endoplasmic reticulum
D) Golgi apparatus
Which of the following is the primary function of microtubules in the cell?
A) Protein synthesis
B) Structural support and intracellular transport
C) DNA replication
D) Membrane transport
Which of the following proteins is essential for the formation of the mitotic spindle during cell division?
A) Actin
B) Tubulin
C) Myosin
D) Keratin
Which of the following is TRUE regarding the role of ribosomes in protein synthesis?
A) They synthesize RNA
B) They are found only in the rough endoplasmic reticulum
C) They link amino acids together to form proteins
D) They degrade misfolded proteins
What is the major role of chaperone proteins in the cell?
A) To assist in DNA replication
B) To help fold proteins into their proper shapes
C) To synthesize RNA
D) To transport proteins across the plasma membrane
Which organelle is responsible for modifying, sorting, and packaging proteins for secretion?
A) Nucleus
B) Golgi apparatus
C) Ribosome
D) Lysosome
What is the end product of the Calvin cycle in photosynthesis?
A) Oxygen
B) Glucose
C) ATP
D) NADPH
Which of the following is a characteristic feature of prokaryotic cells?
A) They lack a plasma membrane
B) They have a true nucleus
C) They lack membrane-bound organelles
D) They have mitochondria
In eukaryotic cells, the primary site of ATP production is the:
A) Nucleus
B) Mitochondrion
C) Golgi apparatus
D) Ribosome
What is the main purpose of the second messenger cAMP in cellular signaling?
A) To activate transcription factors
B) To activate protein kinases
C) To synthesize DNA
D) To degrade cellular proteins
Which of the following molecules can act as a signaling molecule in cell communication?
A) DNA
B) RNA
C) Proteins
D) All of the above
Which process describes the movement of molecules from an area of high concentration to an area of low concentration without the use of energy?
A) Active transport
B) Osmosis
C) Facilitated diffusion
D) Simple diffusion
Which of the following structures is involved in the synthesis of lipids in the cell?
A) Rough endoplasmic reticulum
B) Smooth endoplasmic reticulum
C) Ribosome
D) Golgi apparatus
In which phase of the cell cycle does DNA replication occur?
A) G1 phase
B) S phase
C) G2 phase
D) M phase
Which of the following best describes the structure of the phospholipid bilayer?
A) A double layer of cholesterol molecules
B) A single layer of hydrophilic molecules
C) A double layer with hydrophobic tails and hydrophilic heads
D) A triple layer of proteins
Which of the following molecules is responsible for carrying the genetic information from the DNA to the ribosomes for protein synthesis?
A) rRNA
B) tRNA
C) mRNA
D) snRNA
Which of the following is a characteristic of an enzyme?
A) It is a type of carbohydrate
B) It speeds up chemical reactions
C) It can only function at high temperatures
D) It is used up in the reaction
Which of the following is NOT true about the structure of DNA?
A) It is double-stranded
B) It contains deoxyribose sugar
C) It contains uracil as a base
D) It contains adenine, thymine, cytosine, and guanine
What is the role of RNA polymerase during transcription?
A) It synthesizes RNA from a DNA template
B) It unwinds the DNA double helix
C) It binds to the promoter to begin translation
D) It assembles ribosomes
Which of the following is NOT a stage of mitosis?
A) Anaphase
B) Prophase
C) Metaphase
D) Cytokinesis
What is the role of telomerase in eukaryotic cells?
A) It synthesizes ribosomal RNA
B) It replicates the DNA in the nucleus
C) It extends the telomeres at the ends of chromosomes
D) It repairs damaged DNA
Which of the following is responsible for packaging proteins into vesicles for transport out of the cell?
A) Lysosome
B) Golgi apparatus
C) Smooth endoplasmic reticulum
D) Mitochondria
What is the main function of the nuclear envelope?
A) To allow DNA replication
B) To synthesize RNA
C) To separate the nucleus from the cytoplasm
D) To facilitate protein synthesis
What type of bond is formed between two amino acids during protein synthesis?
A) Ionic bond
B) Peptide bond
C) Hydrogen bond
D) Disulfide bond
Which of the following is NOT involved in the process of translation?
A) mRNA
B) tRNA
C) Ribosome
D) RNA polymerase
Which of the following statements about the cytoskeleton is FALSE?
A) It provides structural support to the cell
B) It is composed of microtubules, microfilaments, and intermediate filaments
C) It helps in cell division and movement
D) It is composed of the cell’s genetic material
Which of the following organelles is responsible for the breakdown of fatty acids?
A) Peroxisomes
B) Lysosomes
C) Ribosomes
D) Golgi apparatus
In the context of gene regulation, what does “epigenetic” refer to?
A) Changes in the DNA sequence
B) The process of protein synthesis
C) Modifications to DNA or histones that affect gene expression
D) The replication of RNA
What is the function of the 5′ cap on eukaryotic mRNA?
A) It stabilizes the mRNA and helps with its export from the nucleus
B) It initiates the translation process
C) It removes introns from the mRNA
D) It facilitates DNA replication
Which of the following is a correct feature of the endoplasmic reticulum (ER)?
A) The smooth ER synthesizes lipids and detoxifies drugs
B) The rough ER is responsible for synthesizing lipids
C) The smooth ER synthesizes proteins for export
D) The rough ER stores genetic material
Which of the following is a characteristic of a prokaryotic cell?
A) A membrane-bound nucleus
B) Mitochondria
C) A nucleoid region instead of a nucleus
D) Ribosomes are absent